textproduct: Quad Cities

KEY MESSAGES

- Seasonal temperatures will remain through the end of the week with a pattern change introducing warming temperatures and increasing humidity into the weekend.

- A more active pattern takes shape Tuesday through Thursday, introducing chances (60-80%) for scattered showers and storms. The severe threat with these storms appear to be limited.

SHORT TERM /THROUGH TUESDAY NIGHT/

Issued at 131 AM CDT Mon Aug 3 2026

Ridging over the area keeps things dry again today with highs climbing back into the low-to-mid 80s. Heading into tonight, our winds shift back southerly as an approaching cold front in association with a longwave trough over the Northern Rockies and Plains shifts into the Minnesota and northwest Iowa. Lows will drop back into the upper 50s and low 60s.

By Tuesday, the cold front reaches eastern Iowa by the late afternoon, bringing some isolated showers and storms (20-40% coverage). The severe threat with these storms should be limited as the overlap in shear and instability will be located right along the front north of Interstate 80 in Iowa, but the level of shear and instability is forecasted to be low with only a 30-50% chance of SBCAPE exceeding 500 J/kg underneath at least 30 knots of 0-6 km bulk shear.

As the cold front continues southeastward into northern Illinois and northeast Missouri Tuesday night, it will stall out and act as a focal point for additional showers and storms (60-80% coverage), mainly along a mid-level F-gen band behind the front. The severe threat is expected to diminish into the evening as surface CAA and loss of daytime heating cut into the available instability, but the potential for heavy rainfall is likely with PWATs exceeding 1.7 inches (60-80% chance per 02.12z LREF guidance).

LONG TERM /WEDNESDAY THROUGH SUNDAY/

Issued at 131 AM CDT Mon Aug 3 2026

Wednesday-Thursday...A shortwave trough will swing into the base of the longwave situated over the Upper Mississippi River Valley on Wednesday, finally pushing the cold front further southeast along with the scattered showers and storms. Areas that receive repeated rounds of storms, especially after rainfall Tuesday night, could see some localized flash flooding which is why the WPC has issued a Slight Risk (Level 2 out of 4) for excessive rainfall for most of the CWA. By Wednesday night, a high pressure shifts into the CWA as convergence aloft continues to dry things out. Isolated showers and storms (20-30% coverage) could stick around in northeast Missouri and west- central Illinois along an area of low-level isentropic upglide near the baroclinic zone Thursday into Thursday night.

Friday-Sunday...The longwave trough axis propagates into the Great Lakes region, providing additional ageostrophic convergence aloft Friday into Saturday. As the high pressure over the region moves eastward, southerly flow will likely return into the weekend and advect in some warmer and more moist air. Highs could climb back into the upper 80s and low 90s by Sunday (50-80% chance per 02.12z LREF run).

AVIATION /18Z TAFS THROUGH 18Z TUESDAY/

Issued at 1225 PM CDT Mon Aug 3 2026

VFR conditions will prevail through the TAF period, with a mix of clouds/sun and light south/southeasterly winds. These conditions will continue through tonight, with winds shifting southwesterly after 12z Tuesday. No sig wx is expected at this time.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.